Hydro One Limited Announces Secondary Offering of Common Shares by the Province of Ontario

May 8, 2017

NOT FOR DISTRIBUTION TO U.S. NEWSWIRE SERVICES OR FOR DISSEMINATION IN THE UNITED STATES

Hydro One Limited ("Hydro One" or the "Company") (TSX:H) announced today that Hydro One, together with the Province of Ontario (the "Province"), have entered into an agreement with a syndicate of underwriters for the secondary offering by the Province (the "Offering"), on a bought deal (firm commitment offering) basis, of 120,000,000 common shares ("Common Shares") of Hydro One at a price of $23.25 per share, for total gross proceeds of $2.79 billion. In addition, the Province has granted the underwriters an over-allotment option, exercisable for a period of 30 days following closing, to purchase up to an additional 12,000,000 Common Shares at the same price per share which, if exercised in full, would increase the gross offering proceeds to approximately $3.07 billion. Hydro One will not receive any of the proceeds from the sale of Common Shares by the Province.

The Offering is being made through a syndicate of underwriters led by RBC Capital Markets and CIBC Capital Markets.

Following completion of the Offering, the Province will continue to hold 296,803,660 Common Shares (284,803,660 Common Shares if the over-allotment option is exercised in full), representing approximately 49.9% of Hydro One's total issued and outstanding Common Shares (47.8% if the over-allotment option is exercised in full).

The Common Shares offered under the Offering will be offered in all provinces and territories of Canada by way of a prospectus supplement to the base shelf prospectus of Hydro One dated March 30, 2016. The Offering will also be extended to Qualified Institutional Buyers in the United States pursuant to the exemptions from registration provided by Rule 144A under the United States Securities Act of 1933, as amended (the "U.S. Securities Act") and corresponding exemptions from registration under state securities laws. The closing is scheduled for May 17, 2017, subject to customary closing conditions. A copy of the base shelf prospectus dated March 30, 2016 is available, and a copy of the prospectus supplement will be available, on SEDAR (www.sedar.com). The base shelf prospectus and the prospectus supplement contain important information about the securities being offered and investors should read such documents before making an investment decision.

No securities regulatory authority has either approved or disapproved of the contents of this news release. The securities being offered have not been, and will not be, registered under the U.S. Securities Act, or any state securities laws, and may not be offered or sold in the United States or to, or for the account or benefit of, any U.S. persons (as defined in Regulation S under the U.S. Securities Act) unless pursuant to an exemption from those registration requirements. This press release is for information purposes only and does not constitute an offer to sell or a solicitation of an offer to buy any securities of Hydro One in the United States or any other jurisdiction.

Forward-Looking Information
This press release may contain "forward-looking information" within the meaning of applicable securities laws. Words such as "expect," "anticipate," "intend," "attempt," "may," "plan," "will", "can", "believe," "seek," "estimate," and variations of such words and similar expressions are intended to identify such forward-looking information. These statements are not guarantees of future performance or actions and involve assumptions and risks and uncertainties that are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed, implied or forecasted in such forward-looking information. Some of the factors that could cause actual results or outcomes to differ materially from the results expressed, implied or forecasted by such forward-looking information, including some of the assumptions used in making such statements, are discussed more fully in Hydro One's filings with the securities regulatory authorities in Canada, which are available on SEDAR at www.sedar.com. Hydro One does not intend, and it disclaims any obligation, to update any forward-looking information, except as required by law.

About Hydro One Limited
We are Ontario's largest electricity transmission and distribution provider with more than 1.3 million valued customers, $25 billion in assets and annual revenues of over $6.5 billion. Our team of 5,500 skilled and dedicated employees proudly and safely serves suburban, rural and remote communities across Ontario through our 30,000 circuit km high-voltage transmission and 123,000 circuit km primary distribution networks. Hydro One is committed to the communities we serve, and has been rated as the top utility in Canada for its corporate citizenship, sustainability, and diversity initiatives. We are one of only four utility companies in Canada to achieve the Sustainable Energy Company designation from the Canadian Electrical Association. We also provide advanced broadband telecommunications services on a wholesale basis utilizing our extensive fibre optic network. Hydro One Limited's common shares are listed on the Toronto Stock Exchange (TSX:H).